Answer:
3.76 m/s
Explanation:
Instantaneous velocity: This can be defined as the velocity of an object in a non uniform motion. The S.I unit is m/s.
v' = dx(t)/dt..................... Equation 1
Where v' = instantaneous velocity, x = distance, t = time.
Given the expression,
x(t) = 28.0 m + (12.4 m/s)t - (0.0450 m/s³)t³
x(t) = 28 + 12.4t - 0.0450t³
Differentiating x(t) with respect to t.
dx(t)/dt = 12.4 - 0.135t²
dx(t)/dt = 12.4 - 0.135t²
When t = 8.00 s.
dx(t)/dt = 12.4 - 0.135(8)²
dx(t)/dt = 12.4 - 8.64
dx(t)/dt = 3.76 m/s.
Therefore,
v' = 3.76 m/s.
Hence, the instantaneous velocity = 3.76 m/s
Answer:
See Explanation
Explanation:
According to Newton's second law of motion, the acceleration of a body is proportional to the net external force that acts on the body.
A body accelerated when it is acted upon by an unbalanced net external force.
When the external forces acting on a body are balanced, the effect of each force is cancelled by the other hence the body is not accelerated according to Newton's second law.
Any object that is launched as a projectile will lose speed and, as a result, altitude, as it travels through the air. The rate at which the object loses speed and altitude depends on the amount of force that way applied to it when it was launched. It is also dependent on the size and shape of the item. This is why something like, say, a football is much faster to fall to the ground than a bullet.
I know I'm a bit late but just in case you still need some of the answers.
1: Oxygen
2: Change in shape
3: Water breaking down into hydrogen and oxygen
4: I think it's Milk but I might be wrong.
I might be wrong about some of them, sorry it's not much.
Answer:
D
Explanation:
because it doesn't agree with the law of definite proportion
and energy can niether be created nor destroyed but can be transformed from one form to another